[LEC] Unit 6: Opportunistic Mycoses

Question 1

Infections in patients with immune deficiencies who would otherwise not be infected

Answer 1

Opportunistic mycoses

Question 2

Endogenous/Exogenous: Part of a normal human flora (microbiota)

Answer 2

Endogenous

Question 3

Endogenous/Exogenous: Fungus does not normally live in/on human body

Answer 3

Exogenous

Question 4

Examples of Endogenous fungi

Answer 4

Candida spp.
Pneumocystis jirovecii

Question 5

Examples of Exogenous fungi

Answer 5

Cryptococcus neoformans
Aspergillus spp.
Zygomycetes

Question 6

Condition caused by Candida albicans

Answer 6

Candidiasis or Moniliasis

Question 7

Causes the most frequent opportunistic fungal infections

Answer 7

Candida spp.

Question 8

Harmless inhabitants of the skin and mucous membranes (RT, GIT, Female Genital tract)

Answer 8

Candida spp.

Question 9

T or F: Normal immune system keeps Candida off body surfaces

Answer 9

F

keeps Candida on

Question 10

Examples of other candida spp.:

Answer 10

○ C. tropicalis
○ C. krusei
○ C. parapsilosis
○ C. glabrata
○ C. gullermondii
○ C. lusitaniae
○ C. kefyr

Question 11

T or F: CD4 is a main defense mechanism of the body against Candida

Answer 11

T

Question 12

The most important risk factor in Candidiasis

Answer 12

Neutropenia

Question 13

Onychomycosis is the infection of what body part?

Answer 13

Nails

Question 14

T or F: Only about 30% of candidemia cases can be proven

Answer 14

F

50%

Question 15

T or F: The mortality of candidemia is 30-40%

Answer 15

T

Question 16

Identify the colors seen in Chrom Agar:

● C. albicans-
● Candida krusei-
● Candida tropicalis-
● Other species-

Answer 16

● C. albicans- green
● Candida krusei- pink
● Candida tropicalis- metallic blue
● Other species- white to mauve

Question 17

Alternative for Chrom Agar

Answer 17

Germ Tube

Question 18

T or F: C. albicans is germ tube (+) in low protein environment

Answer 18

F

high protein

Question 19

Candida spp. that are (+) in Germ Tube Test

Answer 19

C. albicans and C. dubliniensis

Question 20

Example of high protein environment for Germ Tube Test

Answer 20

Plasma / Serum

Question 21

T or F: Cross infections of candidiasis are common among ICU patients

Answer 21

T

Question 22

Treatment of Candidiasis

Answer 22

Amphotericin B (for neutropenic patients)
Fluconazole (nonneutropenic patients)
Nystatin (suppresses intestinal and vaginal candidiasis)
Caspofungin

Question 23

Causative agent of Pneumocystis Pneumonia

Answer 23

Pneumocystis jirovecii

Question 24

T or F: Pneumocystis jirovecii was previously classified as a bacteria

Answer 24

F

protozoa

Question 25

Present in lungs of many mammals, including humans, in persistent but harmless infection

Answer 25

Pneumocystis jirovecii

Question 26

Patients who underwent transplantation are given __________ _______ so that the body will not reject the organ

Answer 26

immunosuppressive agents

Question 27

T or F: Corticosteroid can weaken the immune system

Answer 27

T

Question 28

Causes interstitial pneumonitis in compromised patients

Answer 28

P. jirovecii

Question 29

Treatment and prevention of P. jirovecii

Answer 29

Co-trimoxazole Pentamidine

Question 30

Condition caused by Cryptococcus neoformans

Answer 30

Cryptococcosis or Torulosis

Question 31

Occurs worldwide in soil and in bird droppings

Answer 31

C. neoformans

Question 32

Prominent feature: thick polysaccharide capsule, which causes evasion from phagocytosis

Answer 32

C. neoformans

Question 33

T or F: C. neoformans may disseminate in other organs like the brain, causing meningitis

Answer 33

T

Question 34

T or F: Exudate can be used as a specimen for C. neoformans

Answer 34

T

Question 35

Treatment of C. neoformans

Answer 35

Combination of chemotherapy of Amphotericin B and Flucytosine

Question 36

Infection is always exogenous, it is not transmitted from human to human

Answer 36

C. neoformans

Question 37

Test for C. neoformans that detects enzyme phenol oxidase

Answer 37

Niger Seed Agar

Question 38

Causative agent of Aspergillosis

Answer 38

Aspergillus spp.

Question 39

Aspergilli are worldwide occurring _________, living in soil and on plants; they have small conidia that form aerosols

Answer 39

saprophytes

Question 40

Produce aflatoxins in food

Answer 40

Aspergillus flavus

Question 41

Color of Aspergillus colonies on SDA

Answer 41

gray to green

Question 42

Treatment for Aspergillosis

Answer 42

Amphotericin B, Itraconazole, Flucytosine and Surgery

Question 43

T or F: Aspergillosis can be prevented by avoiding exposure to conidia (new buildings)

Answer 43

T

Question 44

Causative agents of Zygomycosis

Answer 44

Mucor Rhizopus Absidia Rhizomucor

Question 45

It is an invasive disease caused by zygomycetes

Answer 45

Zygomycosis

Question 46

These fungi are ubiquitous thermotolerant saprophyte; spores are present in air and dust

Answer 46

Zygomycosis

Question 47

It is an obsolete polyphyletic taxon

Answer 47

Class Phycomycetes

Question 48

T or F: Spores of Rhizopus remain adhered to the columella thus not easily disseminated

Answer 48

F should be Mucor

Question 49

Have globose sporangia and sporangiophores are not swollen where they merge with the columellae

Answer 49

Absidia

Question 50

Results from germination of the sporangiospores in the nasal passages and invasion of the hyphae into the blood vessels, causing thrombosis, infarction and necrosis

Answer 50

Rhinocerebral mucormysosis

Question 51

This follows inhalation of the sporangiospores with invasion of the lung parenchyma and vasculature

Answer 51

Thoracic mucormysosis